Author Topic: That Dreaded -De-Compressor  (Read 4937 times)

0 Members and 1 Guest are viewing this topic.

wildbill

  • Grand Gearhead
  • *****
  • Posts: 3,282
  • Karma: 1
on: October 03, 2017, 08:48:24 am
Now my songs usually go like this –

https://youtu.be/zP8Ycyor3ss

But wait there’s more like just a couple of days back ::) could be another song..LOL

I was out cruis’in on a nice warm spring day
Just 200 miles on the new bike, with a tad of power at play
Came out of a bend, and went hard on the throttle
I had a noise in the motor, then a power drop followed


I shot an email off to the states, to my old mate GHG
He replied do a compression test and let me know what you see
The test came up at just a cool 60 psi
I was so low on compression that bike was sure to die

GHG instructions were -  Oh so loud and so clear 
 Just pull that right side engine case, and throw that de-compressor gear
So I did another compression test and much to my surprise
It threw a healthy 155 and a huge smile filled my dial

Put the sports muffler back on, and added the ejk too
Got on that new grey bustardo of a bike, and rode the bustard too
Power is back on, and it’s ready to rock and roll,
but something more to think about
That  de-compressor can stop you cold.

And I was pretty well close to that as I crawled into home base! How worried wildbill? Well I thought I might be buying a new bike…LOL


Guaire

  • Grand Gearhead
  • *****
  • Posts: 1,981
  • Karma: 0
Reply #1 on: October 03, 2017, 09:22:43 pm
Nice video. I'll look up your music friends.
ACE Motors - sales & administration


Guaire

  • Grand Gearhead
  • *****
  • Posts: 1,981
  • Karma: 0
Reply #2 on: October 03, 2017, 09:27:55 pm
ACE Motors - sales & administration


Waltair123

  • Scooter
  • **
  • Posts: 30
  • Karma: 0
Reply #3 on: October 03, 2017, 09:28:20 pm
Wildbill, very nicely penned ????
Honda CB450 K5 SuperSport (1972)
RE Classic C5 (2012)


wildbill

  • Grand Gearhead
  • *****
  • Posts: 3,282
  • Karma: 1
Reply #4 on: October 04, 2017, 12:59:58 am
waltair123
I have 3 songs in my collection of an album of C5 classics so far...LOL

https://youtu.be/C5zW3UOhl14


gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 4,485
  • Karma: 0
Reply #5 on: October 04, 2017, 01:14:38 am
    Can you put this one to Music Brother ?    Hehehehe.... ;)

      In from work late ,dragging me arse.   
     The computer screen flashing urgent   
     It wasn't no farce.

     It was old Wildbill again down  in OZ.
     That shiny new Enfield had given him  pause ?

     His number 10 was not living up to the bill.
     Why he claimed it could hardly
     climb a feckin' hill ?!

     He described the symptoms and I thought what a shame.
     That feckin' decompressor  has lived up to it's name!

      To rule things out
     Pull that damn plug I suggested he do.
     It might even  give us a feckin' clue?

       Clean as a whistle is what we found
       No specks of metal
       Nor oil around.

      Go get a gauge
      It took some convincing !
      So off to the store he went
      I KNEW he was wincing

      As I laid there in bed
      I chuckled and thought
      Wildbill's issue is all in his HEAD

      That  pressure is escaping
      As it blows past the cracked open valve
      That lifter is pumped
       And easily solved.

         I've seen this before on many Enfield bikes.
         Instability in the valve train
         Is not what the hydraulic lifter likes !

          It bounces around
          All flipping and such
         
          Thinks it see's lash
          That seal at the exhaust valve
          Certainly can not last.........
             

       

       
     
   

   

 
 

« Last Edit: October 04, 2017, 01:47:53 am by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


wildbill

  • Grand Gearhead
  • *****
  • Posts: 3,282
  • Karma: 1
Reply #6 on: October 04, 2017, 10:40:43 am
GHG
I already gave you credit for putting me on the right path and helping me fix/remove that faulty decompressor..... ;D
atm i'm having a bit of trouble with my musicman... I think he has gone awol :D but I will keep it in mind should he return to base;)
today I tested the bike and after the surgery it is running very sweet. and I am very happy BUT I think you cost me a new bike...L.O.L.


gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 4,485
  • Karma: 0
Reply #7 on: October 05, 2017, 01:24:16 am
  OH NO !   YOU said TEN , not eleven .   Don't go looking for excuses for a new one....   We are gonna keep THIS ONE running for a loooong time. ;D  ;) 
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


Waltair123

  • Scooter
  • **
  • Posts: 30
  • Karma: 0
Reply #8 on: October 05, 2017, 02:40:54 am
????????????
Honda CB450 K5 SuperSport (1972)
RE Classic C5 (2012)


Narada

  • Grand Gearhead
  • *****
  • Posts: 1,434
  • Karma: 0
  • Riding the Madrass Missile!
Reply #9 on: October 05, 2017, 03:59:56 am
Spinal Tap didn't stop at ten, they went all the way to 11! ;D
Realize your Self on a Royal Enfield.

2015 Classic Chrome/Maroon; "Bholenath", Ported head by GHG, AVL Pistons, Hitchcocks H.P. Cams, PC-V, A/T,  Kenda-761's, Koso TNT, Premium EFI Silencer.

2015 Triumph T-100 Orange/Black, TTP Stage-2 induction
2012 Triumph Scrambler / Dauntless M-72D Sidecar.


jefrs

  • Scooter
  • **
  • Posts: 32
  • Karma: 0
Reply #10 on: October 19, 2017, 04:33:59 pm
LMAO  8)

The EFI has a centripetal device that lifts the exhaust valve at low revs. It's a simple and generally trouble free device that frees off at 700-750rpm. BMW also use a similar valve lifter. The exhaust valve will generally try to slam it shut it when you blip the throttle from cold and then the motor picks up. It can be heard if you stop or stall the engine.

Problem with removing it is it is not there for the kick start but so the electric wellie can spin the motor up. Removing it will put excessive strain on the starter motor and may damage the sprag.
If it is acting up then it is probably better to replace it.


Rattlebattle

  • Grand Gearhead
  • *****
  • Posts: 973
  • Karma: 0
Reply #11 on: October 19, 2017, 10:07:59 pm
I have never had any issues with mine, which seldom clacks or otherwise makes known it’s presence. However, I do know of several owners who have removed theirs will no apparent ill effect. I’m not convinced that it is necessary as long as the battery is ok and the owner doesn’t persist in trying to start the engine with a weak battery. I wasn’t aware Beemers use a similar system - which ones?
Sic se res habet: fractum est...


Richard230

  • Grand Gearhead
  • *****
  • Posts: 6,023
  • Karma: 0
Reply #12 on: October 19, 2017, 10:18:47 pm
I have never had any issues with mine, which seldom clacks or otherwise makes known it’s presence. However, I do know of several owners who have removed theirs will no apparent ill effect. I’m not convinced that it is necessary as long as the battery is ok and the owner doesn’t persist in trying to start the engine with a weak battery. I wasn’t aware Beemers use a similar system - which ones?

I believe that the BMW 1993-2013 F/G-650 singles used a similar decompressor system.
2018 16.6 kWh Zero S, 2009 BMW F650GS, 2020 KTM Duke 390, 2002 Yamaha FZ1


gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 4,485
  • Karma: 0
Reply #13 on: October 20, 2017, 01:45:38 am
LMAO  8)

Problem with removing it is it is not there for the kick start but so the electric wellie can spin the motor up. Removing it will put excessive strain on the starter motor and may damage the sprag.
If it is acting up then it is probably better to replace it.


   AND.... I got a Bridge I can sell ya too !   ::) ;D   

 Oh ... what a highly engineered and precise and wonderful centripetal-ily  mechanized thing that is  !   So far Seven years without it ?   I'll get back to you when a problem arises... ;)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


Rattlebattle

  • Grand Gearhead
  • *****
  • Posts: 973
  • Karma: 0
Reply #14 on: October 20, 2017, 01:36:45 pm
Mine stays as long as it behaves; when it starts misbehaving it’s out :). I don’t really see the need anyway; it’s only a 500cc pot. There are plenty of big twins that have much bigger capacity pistons to haul over compression and they don’t need a decompressor. I doubt that BMW would bother now that high cranking output batteries are common.
Sic se res habet: fractum est...